Railway switch operating apparatus



1957 H. L. BONE 2,811,635

RAILWAY SWITCH OPERATING APPARATUS Original Filed Dec. 30, 1950 2 Sheets-Sheet 1 5&1 2o 22 1b 2 70 52 I I as 0 II 2 78 E 48 62 b a: 5 54 7.5 550 Id 3 56a 1e 2 h 5' 28 22 1514 v45a 25 1 6 1a INVENTOR. 4 r Herber L Bozze.

I 57 JU. W..

Oct. 29, 1957 H. L. BONE RAILWAY swx'rcu OPERATING APPARATUS Original Filed Dec. 30, 1950 2 Sheets-Sheet 2 INVENTOR. fikrbel' L 50120. BY

HIS ATTORNEY United States Patent RAILWAY SWITCH OPERATING APPARATUS I Herbert L. Bone, Forest Hills, Pa., assignor to Westinghouse Air Brake Company, Wilmerding, Pa., :1 corporation of Pennsylvania Original application December 30, 1950, Serial No. 203,709, now Patent No. 2,699,853, dated January 18, 1955. Divided and this application April 30, 1953, Serial No. 352,206

7 Claims. (Cl. 246-242) My invention relates to railway switch operating apparatus, and particularly to dual control switch and lock movements wherein means are provided for selectively operating the movement either by power or by hand.

This application is a division of my copending application for Letters Patent of the United States, Serial No. 203,709 filed on December 30, 1950, now Patent No. 2,699,853, dated January 18, 1955, for Railway Switch Operating Apparatus.

In at least one well-known dual control switch and lock movement for railway switches, as shown for example in Letters Patent of the United States No. 2,388,819 granted to me on November 13, 1945 for Railway Switch Operating Apparatus, the means for selecting between hand and power operation includes a clutch mechanism comprising a pivoted shifter yoke operated by a selector lever, and a sleeve splined to the switch operating crankshaft. The sleeve is provided with clutch faces, which upon movement of the sleeve by the shifter yoke selectively engage clutch faces provided on manually operated and motor driven gears rotatably mounted on the crankshaft. The shifter yoke is pivoted at one end and cooperates by way of rollers with the sleeve splined to the crankshaft, the yoke being oscillated about its pivot by an eccentrically positioned pin carried by the selector lever and cooperating with the free end of the yoke. The switch and lock movement described in the aforesaid patent further includes an auxiliary contact mechanism for interrupting the circuit of the drive motor when the selector lever is moved away from the motor operating position toward the manual operating position.

Due to the pounding of the trains over the rails, switch and lock movements installed in the trackway are subject to severe vibrations. Certain parts of the switch movement in the course of time may show signs of wear due to these excessive vibrations. In the dual control mechanism of a switch and lock movement, wear of certain parts may introduce undesirable clearances which affect the positive operation of the mechanism by the selector lever.

An object of my invention is to provide a selective dual control mechanism for a switch and lock movement with take-up means for adjusting the clearances of the parts to insure positive operation of the dual control mechanism.

Another object of my invention is to provide a novel contact mechanism for interrupting the circuit of the drive motor of a switch and lock movement when the dual control mechanism is shifted from the motor operating position toward the manual operating position by the selector lever.

According to my invention, the shifter yoke of the dual control mechanism is pivoted on eccentric bushings so that vertical adjustments may be made with respect to the rollers carried by the yoke and the clutch sleeve splined to the switch operating crankshaft. The eccentric bushings provide a take-up for any manufacturing variances so .that positive operation of the clutch mechanism ICC by the shifter yoke is insured. The shifter yoke is pivoted at one end on the eccentric bushings and cooperates at the other end by way of a tapered pin and tapered slot connection with a selector lever, the rollers cooperating with the splined sleeve being located between the pivot point of the yoke and the pin and slot connection. The eccentric bushings provided for the yoke pivot are so adjusted that horizontal movement of the yoke is minimized in view of the tapered pin and tapered slot connection of the free end of the yoke with the selector lever.

The movement of the shifter yoke of my novel clutch mechanism actuates cut-out contacts in the circuit of the drive motor of the switch and lock movement. The shifter yoke is provided with a cam face which cooperates with a pivoted cam follower rod. The movement of the shifter yoke cam when shifting the clutch mechanism from its motor position to its manual position, will rotate the cam follower rod causing the cut-out contacts to be opened through the medium of a second pivoted rod. The second rod is formed with an adjustable eccentric portion which permits accurate adjustment of the parts so that the cut-out contacts are operated at the proper time.

Other objects and characteristic features of my inven-, tion will become apparent as the description proceeds.

I shall describe one form of a dual control clutch mech anism embodying my invention, and shall then point our the novel features thereof in claims.

In the accompanying drawings:

Fig. 1 is a plan view of dual control clutch mechanism embodying my invention, together with portions of the drive motor and the circuit controller of a switch and lock movement.

Fig. 2 is a sectional view taken along the line II-II of Fig. l.

Fig. 3 is a sectional view taken along the line III- -III of Fig. 1, portions of which are broken away for a better illustration of the parts.

Fig. 4 is a vertical sectional view showing details of the eccentric mounting for the yoke, while g Fig. 5 is an isometric view of the motor cut-out operat-' ing mechanism. I

Referring now in detail to the drawings, the reference numeral 1 designates a housing having end walls 1a and 1b and a bottom wall 10, and provided with a removable cover 2. The housing 1 is fixed, as by bolts 3, to the top of horizontal wall 4 forming a part of a circuit controller housing 5 (only a portion of which is illustrated). The circuit controller housing 5 forms a part of a switch and lock movement similar to that shown and described in the aforesaid Letters Patent of the United States No; 2,388,819. The housing 1 is divided into two sections or compartments 6 and 7 by a vertical wall 1d integral with thebottom wall 10. Suitably journaled in the end wall 1b and the dividing wall 1a aretwo horizontal shafts 8 and 9 having fixed thereto a spacer 10 and gears 11 and 12, and gears 13 and 14 and a spacer 15, respectively, within the compartment 7. The gears 11 and-14 are-in mesh while the teeth of gear 12 mesh with a pinion 16 fixed to the drive shaft of a motor 17, the motor 17 being external of the housing 1, with the drive shaft and pinion 16 extending into the compartment 7 through a suitable opening la in the side wall 1b. The gear 13 meshes with a gear 18 fixed on a rotatable sleeve 19, the sleeve form: ing a portion of a conventional friction clutch generally designated by the reference character 20, the rotation of the *gear being transmitted through the friction clutch'to a worm 21 carried by an extended shaft 21a (Figs.1 and 3) suitably journaled in the end walls 1a and 1d, the rotatable sleeve 19 being journaled on shaft 21a.

Fixed to the top of the dividing wall 1d and to a suit:

. able extension If on theend wall 1a, as by bolts-22, is a top bearing plate 23 having an opening 23a therein which is in vertical alignment with an opening 1g formed in the bottom wall 1c of the housing. Fixed in the opening 1g is a flanged bushing 24, the opening 23a being provided with a bushing 25. Keyed to the bushing 25, as at 26, is a vertical shaft 27, the lower end of which is supported in the bushing 24. Rotatably mounted on the vertical shaft 27 directly above the lower bushing 24 is a worm gear .28 which meshes with the motor driven worm 21. Rotatably mounted on the upper end of the shaft 27 between the bushing 25 and the upper end of a bushing 29, the lower end of which rests on a shoulder 30 formed on the shaft 27, is a bevel gear 31. The bevel gear 31 meshes with a second bevel gear 32 which is fixed as by a set screw 32a to the inwardly extending end of a horizontal tubular shaft 33. The tubular shaft is journaled in a bearing 34 fixed in an opening 111 of a boss lion the housing 1 as by bolts 35. As will hereinafter be more fully described, the tubular shaft is adapted to be rotated approximately 180 by means of a hand-throw lever 36 fixed to the end thereof.

The lower end of the vertical shaft 27 terminates in a crank 37' extending in opposite directions from the shaft. The crank is provided on its under side with a roller 38 and on its upper side with rounded upstanding projections 39. The dependent roller 38 cooperates with a cam slot 40a in an operating rod 40 while each of the projections 39 cooperates with two of three spaced rollers 41 carried by a slide bar 42 in the well-known manner. The operating rod 40 is slidably mounted in the bottom of the housing and is operatively connected at one of its outer ends with the head rod of a switch (not shown). The slide bar 42 is slidably mounted in the bottom of the housing 5 in a position in which it intersects the operating rod at right angles, the left-hand end of the slide bar being provided with a lock box which is not illustrated herein but illustrated and described in my copending application for Letters Patent of the United States, Serial No. 203,708, filed December 30, 1950, for Railway Switch Operating Apparatus.

Means are provided for selectively connecting the bevel gear 31 or the worm gear 28 with the switch operating shaft 27 to permit the switch to be operated either by the hand-throw lever 36 or by the motor 17. To this end a clutch assembly generally designated by the reference character 43 is provided which comprises two sleeves 44 and 45 whichare mounted on the shaft 27 for vertical sliding movement between the two gears 28 and 31, both sleeves being provided with internal splines (not shown) which cooperate with corresponding external splines 47 on the shaft 27 so that said sleeves are rotatable with said shaft; The two sleeves are secured together to form a unitary sleeve provided at its upper and lower ends with outwardly extending flanges 44a and 45a, respectively; Placed about the sleeves 44 and 45 adjacent to the flanges 44d and 45a are two spring cups 48 and 49. The spring cups are substantially Z-shaped in cross-section (Fig. 2), the upper spring cup 48 being formed with an inwardly extending flange 48a, an outwardly extending lip 48b and a dependent sleeve portion 480, while the lower spring cup 49 is formed with an inwardly extending flange 49a and an outwardly extending lip 49b. A coil compress'ion spring 50 surrounding the sleeves 44 and 45 and having one end received within the cup 48 against the flange 48a and the other end received within the cup 49 against the flange 49a, biases the two spring cups 48 and 49 outwardly against the flanges 44a and 45a, respectively, of the two sleeves.

The lower end of the sleeve 45 is formed with double angled teeth .51 (Fig. 3) which cooperate with double angled teeth 52 provided in the hub of the worm gear 28. When the clutch mechanism 43 is in its lower position as illustrated in Figsr2 and 3, the crankshaft 27 will be comeetcd to the worm gear 28 to enable the shaft 27 to 4 be power operated by the motor 17 in the manner hereinafter more fully described.

The upper end of the upper sleeve 44 is formed with a single projection 53 which cooperates with a matching projection 54 on the hub of the bevel gear 31. When the clutch mechanism 43 is in its upper position as illustrated in Fig. 4, the crankshaft 27 will be connected to the bevel gear 31 to permit manual operation of the shaft 27 by the hand-throw lever 36 in the manner hereinafter described.

The clutch assembly 43 is arranged to be moved longitudinally on the crankshaft 27 by means of a shifter yoke 55 so that the crankshaft may be driven either by the worm gear 28 or the bevel gear 31. The shifter yoke 55 comprises two substantially diamond shaped arms 56a and 56b interconnected at their front ends by a cross member 57 and intermediate their ends by a second cross member 58. Fixed to the inner faces of the shifter yoke arm 56a are two spaced rollers 59a and 60a while the shifter yoke arm 56b is similarly provided with two rollers 59b and 60b in horizontal alignment respectively with the rollers 0n the arm 56a. The rollers 59a and 5% are adapted to cooperate with the lip 48b of the spring cup 48 while the rollers 60a and 6915 are adapted to cooperate with the lip 49b of the spring cup 49. For purposes hereinafter appearing the lower edge of the shifter yoke arm 56a is provided with an outwardly extending beveled surface 61, hereinafter referred to as the cam surface 61, while the rear ends a tapered recess 57a which receives a tapered pin 68 fixed in a disc 69. The disc 69 forms a part of a selector lever shaft 70 journaled in the hand-throw lever shaft 33. Fixed to the other end of the shaft 70 is a selector lever 71 interconnected with the hand-throw lever 36 by an interlock generally designated by the reference character 72 which insures the proper sequence of operation of the two levers as fully detailed and described in Letters Patent of the United States No. 1,887,376 for Railway Switch Operating Apparatus, issued on November 8, 1932 to Glen V. Jefferson et al. The position of the selector lever illustrated in Fig. l is the position in which .the vertical shaft 27 will be driven by the motor 17.

With the selector lever 71 in its motor position illustrated in Fig. 1, the shifter yoke 55 will be in the position illustrated in Fig. 3, having been rotated in a counterclockwise direction about its pivot on shaft 66 so that rollers 59a and 59b engaging the lip 48b of the spring cup have moved the sleeves 44 and 45 downwardly on the shaft 27. With the sleeves 44 and 45 in their lower. positions as illustrated in Fig. 2, the double angled teeth 51 on the sleeve 45 are in mesh with the double angled teeth 52 in the hub of the worm gear 28. The vertical shaft 27 is thus, rotated by the motor 17 through the reduction gearing formed by the pinion 16, gears 12, 11, 14, 13 and 18, and the worm 21, the worm gear 28, through the motor clutch formed by the double angled teeth 51 and 52, and the sleeve 45 splined to the shaft. Should it bedesirable to operate the switch. movement by the hand-throw lever 36, the selector lever 71 is first rotated approximately to its manual position, thereby rotating the shaft 70. The disc 69, and pin 68 received within the slot 57a of the shifter yoke, will be rotated 180 to rotate the shifter yoke in a clockwise direction about the shaft 66 to its manual position as shown in Fig. 4. The rotation of the shifter yoke in a clockwise direction will bring the rollers 60a and 60b of the yoke into abutment with the lip 49b of the spring cup 49, thereby moving the spring cup upwardly. The upward movement of the spring cup 49 tends to bias the spring 50, moving the upper spring cup 48 and the sleeves 44 and 45 upwardly. The upward movement of the sleeves 44 and 45 will disengage the teeth 51 of the sleeve 45 from the teeth 52 of the worm gear hub at the same time the projection 53 on the sleeve 44 aligns with the projection 54 on the bevel gear 31 so that the vertical shaft 27 is now connected by the splined sleeve 44 to the bevel gear 31. Rotation now of the handthrow lever 36 will rotate the shaft 33 and the bevel gear 32 meshing with the bevel gear 31.

One of the features of the dual control mechanism thus far described is the mounting of the shifter yoke 55 on the eccentric bushings 67a and 67b and the provision of the rearwardly extending projections 62a and '62]; on the arms 56a and 56b. The eccentric bushings 67a and 67b provide a vertical adjustment for the pivot point of the shifter yoke 55 which will permit the proper vertical adjustment of the rollers 59a, 59b and 60a, 60b with respect to the lips 48b and 49b, respectively, of the two spring cups, the eccentric bushings being also adjustable to take up any manufacturing variations in the various parts. The rearwardly extending projections 62a and 62b on the shifter yoke cooperate with the inner wall 1k of the housing making it necessary for the bushings to be assembled and adjusted so that rotation of the bushings around their centers will be toward the selector lever and not toward the wall 1k in view of the tapered pin 68 and slot 57a. Since the pin 68 is tapered any excessive horizontal motion of the yoke would introduce undesirable vertical clearances between the pin and its receiving recess. The extending projections 62a and 62b are such that if the eccentric bushings are fixed so that the segment of motion around their centers is toward the inner housing wall 1k, the yoke could not be mounted on the shaft due to insufficient clearance between the shaft and the inner wall.

Since the shifter yoke 55 is actuated at its extreme end by the selector lever 71, manufacturing variations have much less effect on the location of the rollers 59a, 59b and 60a, 60b with relation to the splined sleeves 48 and 49 than in the case where a cam actuating the yoke was intermediate the yoke pivot and the load bearing rollers. The loads on the shaft 66 and the tapered pin 68 are also less, thereby reducing the wear on these parts and reducing the friction. Less efifort is therefore required to operate the selector lever.

Referring now to Figs. 1 and 2 of the drawings, motor cut-out contacts 73a and 73b in the electrical circuit (not shown) of the motor 17 are suitably fixed to the end wall of the circuit controller housing 5 and are actuated upon movement of the shifter yoke 55 by the selector lever 71, the action being such that when the selector lever 71 is moved from its motor position toward its manual position, the motor cut-out contacts will be opened, thereby opening the circuit of the motor 17, and when the selector lever is moved from its manual position to its motor position, the motor contacts will be permitted to close so that the motor 17 may again be energized.

For the purposes of actuating the motor cut-out contacts 73a and 73b, a horizontal shaft 74 is suitably journaled in one side of the top bearing plate 23. Threaded through the rearwardly extending end of the shaft 74 is a cam follower rod 75, Figs. 1 and 2, the lower end of which is provided with a beveled surface 76 which engages the cam surface 61 on the yoke 55. The cam follower rod '75 may be vertically adjusted with respect to the cam surface and fastened in place by means of a locknut 77. Threaded through the forwardly extending end of the shaft 74 is a cut-out adjuster rod 78 provided at its lower end with an eccentric portion 79. The cut-out adjuster rod 78 may be adjusted with respect to the position of the eccentric portion 79 and fixed in place by a locknut 80.

Threaded into a suitable opening in the, end wall 1a of the housing 1, is a pipe 81 locked in place by a locknut 82, one end of the pipe being within the housing 1 and capped by a perforated cap 81a while the other end abuts the end wall of the circuit controller housing 5 and in registry with an opening 5a in that housing. A waterproof seal 83 is provided for the opening 5a by a felt washer which is compressed against the housing 5 by a washer and locknuts, not otherwise designated. Longitudinally disposed within the pipe 81 and extending into the housings 1 and 5 is a push rod 84 made of insulation material. Pinned to push rod 84 within the pipe 81 is a spring retaining collar 85. Disposed about the push rod and between the housing 5 and the collar 85 is 'a coil spring 86 tending to bias the push rod 84 toward the right. It will be noted that the end of the push rod 84 within the housing 5 abuts the cut-out contact finger 73a while the other end of the rod 84 abuts the eccentric portion 79 of the cut-out adjuster rod 78. By turning the cut-out adjuster rod the eccentric portion of the rod may be brought to bear against the rod so that when the shifter yoke 55 is in the motor position illustrated in Fig. 2, the eccentric portion 79 of the adjuster rod will be engaged by the push rod to hold the shaft 74 in its counterclockwise rotated position so that the beveled surface 76 of the cam follower rod engages the cam surface 61 on the shifter yoke.

When the selector lever 71 is in its motor position, the cut-out contacts 73a--73b will be closed as illustrated in Figs. 1 and 2. Should the selector lever 71 be moved toward itsmanual position, the shifter yoke 55 will be rotated in the manner described, thereby moving the cam surface 61 upwardly relative to the cam follower rod 75. The camming surfaces 61 and 76 will cause the cam follower rod to be rotated in a clockwise direction (Fig. 2), thereby moving the adjuster rod 78 in the same direction. The eccentric portion 79, engaging the end of the push rod 84, will move the push rod toward the left against the bias of spring 86 to open the cut-out contacts 7311-7311. A return of the shifter yoke 55 to its motor position by the return of the selector lever will permit the spring 86 to return the push rod 84 and the rods 75 and 78 to the positions illustrated in Fig. 2, the cut-out contacts 73a73b again closing.

The dual control mechanism hereinbefore described may be used for right-hand or left-hand installations alongside the railroad switch. The mechanism as described is for a right-hand installation. To change from the right-hand installation assembly illustrated to a left-hand installation assembly, the top bearing plate 2 is first removed so that the shifter yoke 55 may be reversed. The hand-throw bevel gear 32 is then loosened by removing the screw 32a. The complete hand-throw and selector lever assembly may then be removed by removing the bolts 35 which hold the bearing 34 to the front wall of the housing 1. The shifter yoke 55 is then removed by pulling out the shaft 66, and the yoke support 63 removed by unscrewing the bolts 64. The yoke support may now be bolted to the opposite side of the housing. The hand-throw and selector lever assembly may then be bolted to the opposite side of the housing and the hand-throw bevel gear 32 again fixed to the shaft 31. Both arms of the shifter yoke 55 are formed with a cam surface 61 to operate the cut-out contacts 73a-73b.

Although I have herein shown and described only one form of dual control clutch mechanism embodying my invention, it is understood that various changes and modifications may be made therein within the scope of the appended claims without departing from the spirit and scope of my invention.

Having thus described my invention, what I claim is:

1. In railway switch operating apparatus having a switch actuating shaft, manual and power means for driv- 7 ing said shaft, and dual control means for selectively connecting said manual and said power driving means to said shaft, said dual control means including a member movable to a first extreme position to connect the manual driving means to said shaft and to a second extreme position to connect the power driving means to said shaft, a circuit controller, comprising, a cam surface on said movable member, a pivoted cam follower cooperating with said cam surface and rotatable thereby when said member is moved from its second extreme position toward its first extreme position, an eccentric member pivoted with said cam follower and rotatable therewith,

normally closed electrical contacts, and a push rod adapted t to be moved longitudinally by said eccentric member upon rotation thereof to open said electrical contacts, saideccentric member being adjustable to vary the degree of longitudinal movement of said push rod.

2. In railway switch operating apparatus having a switch actuating shaft, manual and power means for driving said shaft, and dual control means for selectively connecting said manual and said power driving means to said shaft, said dual control means including a member movable to a first extreme position to connect the manual driving means to said shaft and to a second extreme position to connect the power driving means to said shaft, the combination comprising, a cam surface on said movable member, a pivoted cam follower cooperating with said cam surface and rotatable thereby when said member is moved from its second extreme position toward its first extreme position, said cam follower being adjust able with respect to said cam surface to vary the degree of movement required by said movable member toward its first extreme position before rotation of said cam follower by said cam surface; an eccentric member pivoted with said cam follower and rotatable therewith, normally closed electrical contacts, and a push rod adapted to be moved longitudinally by said eccentric member upon rotation thereof to open said electrical contacts, said eccentric member being adjustable to vary the degree of longitudinal movement of said push rod.

3. In railway switch operating apparatus having a switch actuating shaft, manual and power means for driving said shaft, and dual control means for selectively connecting said manual and said power driving means to said shaft, said dual control means including a member movable to a first extreme position to connect the manual driving means to said shaft and to a second extreme position to connect the power driving means to said shaft, a circuit controller, comprising, a cam surface on said movable member, a pivoted cam follower cooperating with said cam surface and rotatable thereby in a first direction when said member is moved from its second extreme position toward its first extreme position, an eccentric member pivoted with said cam follower and rotatable therewith, a push rod abutting said eccentric member and movable in one direction by said eccentric member upon rotation thereof in the first direction, biasing means tending to move said push rod in an opposite direction to rotate said eccentric member and said cam follower in a second direction, and electrical contacts cooperating with said push rod and actuated thereby when said push rod is moved in the one direction by said eccentric member, said eccentric member being adjustable to vary the degree of movement of said push rod.

4. A circuit controller comprising a cam member movable between two extreme positions, a cam follower cooperating with said cam member and rotatable thereby in a first direction when said cam member is moved from one extreme position toward its other extreme position, a member pivoted with said cam follower and rotatable therewith, said pivoted member having an eccentric portion; a push rod abutting the eccentric portion of said pivoted member and adapted to be moved longitudinally thereby in one direction when said pivoted member is rotated in said first direction, resilient means cooperating with said push rod tending to bias said push rod in an opposite direction to rotate said pivoted member and said cam follower in a second direction, and electrical contacts actuated by said push rod upon movement thereof in .said onepdirection, said eccentric portion of the pivoted member being adjustable relative to said push rod to vary-the degree of longitudinal movement of said push rod.

5. A circuit controller comprising a cam, member movable between two extreme positions, a cam follower cooperating with said cam member and rotatable thereby in a first direction when said cam member is moved from one extreme position toward its other extreme position, said cam follower being adjustable with respect to said cam member to vary the degree of movement required by said cam member toward its other extreme position before rotating said cam follower; a member pivoted with said cam follower and rotatable therewith, said pivoted member having an eccentric portion; a push rod abutting the eccentric portion of said pivoted member and adapted to be moved longitudinally thereby in one direction when said pivoted member is rotated in said first direction, resilient means cooperating with said push rod tending to bias said'push rod in an opposite di-- rection to rotate said pivoted member and said cam follower in a second direction, and electrical contacts actuated by said push rod upon movement thereof in said one direction, said eccentric portion of the pivoted member being adjustable relative to said push rod to vary the degree of longitudinal movement of said push rod.

6. In railway switch operating apparatus having a switch actuating shaft, power and manual means for driving said shaft, dual control means comprising two gear wheels rotatably mounted on said shaft in spaced relation, each gear wheel cooperating with one of said driving means; clutch faces on said gear wheels in confronting relation, a shiftable sleeve splined to the shaft between said gear wheels and having clutch faces on both ends thereof, the clutch faces on the power driven gear wheel and the corresponding sleeve end having double angled teeth; a shaft, eccentric bushings rotatably mounted on said shaft, a shifter yoke mounted at one end on said bushings and cooperating with said sleeve, a tapered recess in the free end of said yoke, a tapered pin in said recess, and a selector lever for moving said pin in an orbital path to pivot said yoke to two extreme positions to slide said sleeve to one extreme position in which the clutch face on the manually driven gear is engaged by the clutch face of the corresponding end of the sleeve and to a second extreme position in which the clutch face of the power driven gear is engaged by the clutch face on the corresponding end of the sleeve, the segment of arcuate movement of said bushings about their centers being toward said tapered pin; the slope of the base portions of said clutch face teeth being such that the upward reaction due to the camming action of the base portions of said teeth is minimized to prevent disengagement of the power driven clutch faces, the slope of the end portions of 'said clutch face teeth being such that the upward reaction due to the camming action of the end portions of the teeth tends to disengage the clutch faces when said shifter yoke is moved from its second extreme position toward its first extreme position, the combination comprising, a cam surface on said shifter yoke, a pivoted cam follower cooperating with said cam surface and rotatable thereby when said yoke is moved from the second extreme position toward the first ex treme position, an eccentric member pivoted with said cam follower and movable therewith, normally closed electrical contacts, and a push rod adapted to be moved longitudinally by said eccentric member upon rotation of said member to open said electrical contacts, said eccentric member being adjustable to vary the longitudinal movement of said push rod.

7. In combination with railway switch operating apparatus having a switch actuating shaft, power and manual means for driving said shaft, dual control means comprising two gear wheels rotatably mounted on said shaft in spaced relation, each gear wheel cooperating with one of said driving means; clutch faces on said gear wheels in confronting relation, a shiftable sleeve splined to the shaft between said gear wheels and having clutch faces on both ends thereof, the clutch faces on the power driven gear wheel and the corresponding sleeve end having double angled teeth; a shaft, eccentric bushings rotatably mounted on said shaft, a shifter yoke mounted at one end on said bushings and cooperating with said sleeve, a tapered recess in the free end of said yoke, a tapered pin in said recess, a selector lever for moving said pin in an orbital path to pivot said yoke to two extreme positions to slide said sleeve to one extreme position in which the clutch face on the manually driven gear is engaged by the clutch face of the corresponding end of the sleeve and to a second extreme position in which the clutch face of the power driven gear is engaged by the clutch face on the corresponding end of the sleeve, the segment of arcuate movement of said bushings about their centers being toward said tapered pin; the slope of the base portions of said clutch face teeth being such that the upward reaction due to the camming action of the base portions of said teeth is minimized to prevent disengagement of the power driven clutch faces, the slope of the end portions of said clutch face teeth being such that the upward reaction due to the cam- 10 ming action of the end portions of the teeth tends to disengage the clutch faces when said shifter yoke is moved from its second extreme position toward its first extreme position, a circuit controller, comprising, a cam surface on said shifter yoke, a pivoted cam follower cooperating with said cam surface and rotatable thereby when said yoke is moved from the second extreme position toward the first extreme position, said cam follower being adjustable with respect to said cam surface to vary the degree of movement required by said shifter yoke toward its first extreme position before said follower is rotated by said cam surface; an eccentric member pivoted with said cam follower and movable therewith, normally closed electrical contacts, and a push rod adapted to be moved longitudinally by said eccentric member upon rotation of said member to open said electrical contacts, said eccentric member being adjustable to vary the longitudinal movement of said push rod.

References Cited in the file of this patent UNITED STATES PATENTS Laze Sept. 4, 1951 

